Crab sticks are processed sea food made of surimi (or most of the time finely pulverized white fish flesh). It is shaped and cured to resemble snow crab legs. They are usually coloured red and rectangular-oblong in shape. Small strings of the crab sticks can be neatly pulled and torn out in a similar manner to string cheese. The smell of crab sticks is similar to seafood products, having a sweet, salty and highly umami taste. Crab sticks are cooked in its curing process and they can be eaten directly from a package.
Process
First, lean meat from fish is separated or minced. In order to eliminate undesirable odours, the meat may then be rinsed several times. The resulting meat is then beaten and pulverized to form a gelatinous paste. The gelatinous paste is mixed with differing proportions of additives such as starch, egg white, salt, sugar, vegetable oil, sorbitol, soy protein and seasonings, depending on the desired texture and flavour of the final product If the surimi is to be packed and frozen, food-grade cryoprotectants are added while the meat paste is being mixed. Under most circumstances, surimi is immediately processed, formed and cured into surimi products at the time it is produced.
Bacteria is the main cause of seafood spoilage. Millions of bacteria are present in the surface slime, gills, and gut of living seafood species. When seafood species die, they produce fishy odours and flavours, and discolourations. This is caused by bacteria. They invade the flesh through the gills, along blood vessels, and directly through the skin and belly cavity lining in the flesh. If food poisoning bacteria are present, they can multiply and cause illness when the seafood is eaten.
Many different enzymes are present in living seafood species. They help build tissue, contract and relax muscles, and digest food. When seafood species die, enzymes continue to work and start to breakdown the flesh. This causes the flesh to soften and lowering the quality. Enzymes also produce more food for bacteria to feed on, increasing rate of spoilage.
Oxygen in the air can attack unsaturated oils or, seafood causing rancidity, off-odors and off-flavors. This is especially important in fatty fish such as salmon and mackerel.
High temperatures speed spoilage and low temperatures slow spoilage. When temperature is increased from 32ºF to 40ºF, it will double the rate of spoilage and cuts the shelf life in half.
Sanitation is also important. Contamination of seafood by bacteria from dirty ice, containers and surfaces can increase the number of bacteria on seafood and speed spoilage. Contamination with food poisoning bacteria can cause illness when the seafood is eaten. Keeping seafood handling and storage equipment clean reduces bacterial contamination and slows spoilage.
Thawing
Thaw frozen seafood by placing it in the refrigerator overnight. If it has to be thawed quickly, it can be immersed in cold water (with seafood sealed in a plastic bag) or microwaved on "defrost" settling (stop the defrost cycle while seafood is still icy but pliable).
| Microorganism | Illness | Seafood involved |
| Aeromonas hydrophila | Gastroenteritis | Raw oysters |
| Clostridium botulinum | Botulism | Smoked, salted and fermented seafoods |
| Plesiomonas shigelloides | Gastroenteritis | Raw and under cooked oysters, salt mackerel |
| Vibrio hollisae | Gastroenteritis | Raw seafoods |
| Vibrio mimicus | Gastroenteritis | Raw oysters, boiled crayfish |
| Vibrio parahaemolyticus | Gastroenteritis | Raw oysters, contaminated cooked seafood |
| Vibrio vulnificus | Septicemia | Raw oysters |
| Microorganism | Illness | Seafood involved |
| Pathogenic Escherichia coli | Gastroenteritis | Contaminated cooked crabmeat |
| Salmonella typhi | Typhoid fever | Raw oysters |
| Vibrio cholerae O1 | Cholera | Raw oysters, contaminated cooked crab |
| Vibrio cholerae non-O1 | Gastroenteritis | Raw oysters |
| Hepatitis A virus | Infectious hepatitis | Raw shellfish |
| | Gastroenteritis | Raw and steamed shellfish |
| Microorganism | Illness | Seafood Involved |
| Clostridium perfringens | Gastroenteritis | Cooked seafood held below 140°F |
| Listeria monocytogenes | Septicemia | Possibly shellfish and raw fish |
| Salmonella | Gastroenteritis | Contaminated cooked seafood held at 40-140°F |
| Shigella | Gastroenteritis | Contaminated cooked seafood held at 40-140°F |
| Staphylococcus aureus | Gastroenteritis | Contaminated cooked seafood held at 40-140°F |
(Vibrio parahaemolyticus and Vibrio vulnificus are sensitive to various essential oils.)
The Food and Drug Administration issued an advisory (to state and local regulatory agencies) recommending that fish served raw, marinated, or partially cooked should be blast- frozen to -31ºF for 15 hours, or frozen by regular means to -10º or below for seven days. This does not insure its safety from bacteria, it only kills parasites.
“The term "fish" /seafood include all fresh or saltwater finfish, molluscan shellfish, crustaceans, and other forms of aquatic animal life.” (
Fish and shellfish have many health benefits containing high-quality protein and other essential nutrients. They are also low in saturated fat and contain omega-3 fatty acids. However, they contain mercury in trace amount and it poses health concerns. The risks from mercury in fish and shellfish depend on the amount of fish and shellfish eaten and the levels of mercury in the fish and shellfish. Some fish and shellfish contain higher levels of mercury (depending on what the fish/shellfish eats) that can harm a fetus or a child’s developing nervous system.
Mercury occurs naturally in the environment. Another source is through released air pollutants from industrials. Mercury falls from the air and can accumulate in streams and oceans, turning into methylmercury in the water. This form of mercury is harmful to an unborn baby and a young child. Fish absorb methylmercury as they feed in these waters building up in them.
Some examples of seafood with high levels of mercury and should not be eaten are shark, swordfish, king mackerel and tilefish.